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Socrates
Socrates (c. 470–399 bce) was also widely considered to be a Sophist, though he did not teach for money and his aims were entirely different from theirs. Although there is a late tradition according to which Pythagoras invented the word philosopher, it was certainly through Socrates—who insisted that he possessed no wisdom but was striving for it—that the term came into general use and was later applied to all earlier serious thinkers. In fact, all of the records of Socrates’ life and activity left by his numerous adherents and disciples indicate that he never tried to teach anything directly. But he constantly engaged in conversations with everybody—old and young, high and low—trying to bring into the open by his questions the inconsistencies in their opinions and actions. His whole way of life rested on two unshakable premises: (1) the principle never to do wrong nor to participate, even indirectly, in any wrongdoing and (2) the conviction that nobody who really knows what is good and right could act against it. He demonstrated his adherence to the first principle on various occasions and under different regimes. When, after the Battle of Arginusae (406 bce), the majority of the Athenian popular assembly demanded death without trial for the admirals, Socrates, who on that day happened to be president of the assembly (an office changing daily), refused to put the proposal to a vote because he believed it was wrong to condemn anyone without a fair trial. He refused even though the people threatened him, shouting that it would be terrible if the sovereign people could not do as they pleased.
When, after the overthrow of democracy in Athens in 404 bce, the so-called Thirty Tyrants, who tried to involve everybody in their wrongdoing, ordered him to arrest an innocent citizen whose money they coveted, he simply disobeyed. This he did despite the fact that such disobedience was even more dangerous than disobeying the sovereign people had been at the time of unrestricted democracy. Likewise, in the time of the democracy, he pointed out by his questions the inconsistency of allowing oneself to be swayed by the oratory of a good speaker instead of first inquiring into his capability as a statesman, whereas in private life a sensible citizen would not listen to the oratory of a quack but would try to find the best doctor. When, after the overthrow of democracy, the Thirty Tyrants had many people arbitrarily executed, Socrates asked everybody whether a man was a good shepherd who diminished the number of sheep instead of increasing it; and he did not cease his questioning when Critias, the leader of the Thirty Tyrants, warned him to take heed not to diminish the number of sheep by his own—Socrates’—person. But the most fundamental inconsistency that he tried to demonstrate everywhere was that most people by their actions show that what they consider good, wonderful, and beautiful in others—such as, for instance, doing right at great danger to oneself—they do not consider good for themselves, and what they consider good for themselves they despise and condemn in others. Although these stands won him the fervent admiration of many, especially among the youth, they also caused great resentment among leading politicians, whose inconsistencies and failings were exposed. Although Socrates had survived unharmed through the regime of the Thirty Tyrants—partly because it did not last long and partly because he was supported by some close relatives of their leader, Critias—it was under the restored democracy that he was accused of impiety and of corrupting the youth and finally condemned to death, largely also in consequence of his intransigent attitude during the trial.
After Socrates’ death his influence became a dominating one through the greater part of the history of Greek and Roman philosophy down to the end of antiquity, and it has been significant ever since. Many of his adherents—Plato first among them, but also including the historian Xenophon (431–c. 350 bce)—tried to preserve his philosophical method by writing Socratic dialogues. Some founded schools or sects that perpetuated themselves over long periods of time: Eucleides of Megara (c. 430–c. 360 bce) emphasized the theoretical aspects of Socrates’ thought (see Megarian school), and Antisthenes (c. 445–c. 365 bce) stressed the independence of the true philosopher from material wants. The latter, through his disciple Diogenes of Sinope (died c. 320 bce), who carried voluntary poverty to the extreme and emphasized freedom from all conventions, became the founder of the sect of the Cynics. Aristippus of Cyrene (c. 435–366 bce), traditional founder of the Cyrenaic school, stressed independence from material goods in a somewhat different way, declaring that there is no reason why a philosopher should not enjoy material goods as long as he is completely indifferent to their loss. Although Aristippus renounced his son because he led a dissolute life, the school that he founded (through his daughter and his grandson) was hedonistic, holding pleasure to be the only good.
Plato
By far the most important disciple of Socrates, however, was Plato, a scion of one of the most noble Athenian families, who could trace his ancestry back to the last king of Athens and to Solon (c. 630–c. 560 bce), the great social and political reformer.
Life
As a very young man, Plato became a fervent admirer of Socrates in spite of the latter’s plebeian origins. Contrary to his master, however, who always concerned himself with the attitudes of individuals, Plato believed in the importance of political institutions. In his early youth he had observed that the Athenian masses, listening to the glorious projects of ambitious politicians, had engaged in foolhardy adventures of conquest, which led in the end to total defeat in the Peloponnesian War (431–404 bce). When, in consequence of the disaster, democracy was abolished, Plato at first set great hopes in the Thirty Tyrants—especially since their leader, Critias, was a close relative. But he soon discovered that—to use his own words—the despised democracy had been gold in comparison with the new terror. When the oligarchy was overthrown and the restored democracy, in 399 bce, adopted a new law code—in fact, a kind of written constitution containing safeguards against rash political decisions—Plato again had considerable hope and was even inclined to view the execution of Socrates as an unfortunate incident rather than a logical consequence of the new regime. It was only some years later, when demagogy appeared to raise its head again, that he “despaired and was forced to say that things would not become better in politics unless the philosophers would become rulers or the rulers philosophers.” He wrote a dialogue, the Gorgias, violently denouncing political oratory and propaganda, and then traveled to southern Italy in order to study political conditions there. Again, however, he found the much-vaunted dolce vita of the Greeks there, in which the rich lived in luxury exploiting the poor, much worse than in the democracy at Athens. But at Syracuse he met a young man, Dion (c. 408–354 bce)—brother-in-law of the ruling tyrant, Dionysius I (c. 430–367 bce)—who listened eagerly to his political ideas and promised to work for their realization if any occasion should arise. On his return to Athens, Plato founded the Academy, an institution for the education of philosophers, and in the following years he produced, besides other dialogues, his great work, the Republic, in which he drew the outlines of an ideal state. Because it is the passions and desires of human beings that cause all disturbances in society, the state must be ruled by an elite that governs exclusively by reason and is supported by a class of warriors entirely obedient to it. Both ruling classes must have no individual possessions and no families and lead an extremely austere life, receiving the necessities of life from the working population, which alone is permitted to own private property. The elite receives a rigid education to fit it for its task. At the death of Dionysius, Dion induced Plato to come to Syracuse again to try to persuade Dionysius’s successor, Dionysius II (flourished 4th century bce), to renounce his power in favor of a realization of Plato’s ideals. But the attempt failed, and in his later political works, the Statesman and the Laws, Plato tried to show that only a god could be entrusted with the absolute powers of the philosopher-rulers of his republic. Human rulers must be controlled by rigid laws, he held—though all laws are inevitably imperfect because life is too varied to be governed adequately by general rules. But the Laws still placed strict restrictions on the ownership of property.
Philosophy
In the field of theoretical philosophy, Plato’s most influential contribution was undoubtedly his theory of Forms, which he derived from Socrates’ method in the following way: Socrates, in trying to bring out the inconsistencies in his interlocutors’ opinions and actions, often asked what it is that makes people say that a certain thing or action is good or beautiful or pious or brave; and he asked what people are looking at when they make such statements. Plato sometimes, in his dialogues, made Socrates ask what is the eidos, or idea—i.e., the image—that a person has before him when he calls something “good.” A definite answer is never given, however, because no abstract definition would be adequate, the purpose being rather to make the interlocutor aware of the fact that he somehow does look at something indefinable when making such statements.
What was at first simply a way of somehow expressing something that is difficult to express developed into a definite theory of Forms when Plato made the discovery that something similar could be observed in the field of mathematics. No two things in the visible world are perfectly equal, just as there is nothing that is perfectly good or perfectly beautiful. Yet equality is one of the most fundamental concepts not only in mathematics but also in everyday life—the foundation of all measurement. Hence, like the notion of the good and the beautiful, it appears to come from a different world, a world beyond the senses, a world that Plato then called the world of Forms. Further intimations of such a realm beyond the immediate realm of the senses may be found in the fact that, in construing a system of knowledge, people constantly prefer what is more perfect to what is less perfect—i.e., what is formed and thus recognizable to what is not, what is true to what is false, a sound logical conclusion to a logical fallacy, even an elegant scientific demonstration to a clumsy one, without considering the former as good and the latter as bad.
According to Plato, all of the things that people perceive with their senses are but very imperfect copies of the eternal Forms. The most important and fundamental Form is that of the Good. It is “beyond being and knowledge,” yet it is the foundation of both. “Being” in this context does not mean existence, but something specific—a human, a lion, or a house—being recognizable by its quality or shape.
Knowledge begins with a perception of these earthly shapes, but it ascends from there to the higher realm of Forms, which is approachable to the human mind. In the famous myth of the cave in the seventh book of the Republic, Plato likened the ordinary person to a man sitting in a cave looking at a wall on which he sees nothing but the shadows of real things behind his back, and he likened the philosopher to a man who has gotten out into the open and seen the real world of the Forms. Coming back, he may be less able to distinguish the shades because he has been blinded by the light outside; but he is the only one who knows reality, and he conducts his life accordingly.
In his later dialogues, especially the Theaetetus, Plato criticized an empiricist theory of knowledge, anticipating the views of 17th-century English philosophers such as Thomas Hobbes (1588–1679). In the Timaeus, Plato tried to construct a complete system of physics, partly employing Pythagorean ideas.
Aristotle
After Plato’s death, the Academy continued to exist for many centuries under various heads. When Plato’s nephew Speusippus (died c. 338 bce) was elected as his successor, Plato’s greatest disciple, Aristotle (384–322 bce), left for Assus, a Greek city-state in Anatolia, and then went to the island of Lesbos. But soon thereafter he was called to the Macedonian court at Pella to become the educator of the crown prince, who later became Alexander the Great (356–323 bce). After Alexander became king, Aristotle returned to Athens and opened there a school of his own, the Lyceum, whose members were known as Peripatetics.
Philosophy
Aristotle became a member of the Academy at the age of 17, in the year 367 bce, when the school was under the acting chairmanship of Eudoxus of Cnidus (c. 395–c. 342 bce), a great mathematician and geographer (Plato was away in Sicily at the time). It is a controversial question as to how far Aristotle, during the 20 years of his membership in the Academy, developed a philosophy of his own differing from that of his master. But two things can be considered as certain: (1) that he soon raised certain objections to Plato’s theory of Forms, for one of the objections attributed to him is discussed in Plato’s dialogue Parmenides, which Plato must have written soon after his return from Sicily, and (2) that it was during his membership in the Academy that Aristotle began and elaborated his theoretical and formal analysis of the arguments used in various Socratic discussions—an enterprise that, when completed, resulted in the corpus of his works on logic. Aristotle rightly claimed to have invented this discipline; indeed, until rather recent times it was said that he completed it in such a way that hardly anything could be added.
Certainly quite some time before his return to Athens to open a school of his own, Aristotle declared that it is not necessary to assume the existence of a separate realm of transcendent Forms, of which the individual things that human beings perceive with their senses are but imperfect copies; that the world of perceived things is the real world; and that, in order to build up a system of knowledge about certain types or groups of things, it is necessary merely to be able to say that something is generally true of them. Thus, it would be wrong to say that, having abandoned the theory of Forms, Aristotle was left with a completely contingent world. The last chapters of his Posterior Analytics show, on the contrary, that he merely replaced Plato’s transcendent Forms with something (katholou) corresponding to them that the human mind can grasp in individual things.
Aristotle retained another important element of the theory of Forms in his teleology, or doctrine of purposiveness. According to Plato, individual things are imperfect copies of perfect Forms. Aristotle pointed out, however, that all living beings develop from an imperfect state (from the seed, the semen, through the germinating plant, or embryo, to the child and young adult) to the more perfect state of the fully developed plant or the full-grown mature animal or human—after which they again decay and finally die, having reproduced. But not all individuals reach the same degree of relative perfection. Many of them die before reaching it; others are retarded or crippled or maimed in various ways in the process. It is, therefore, of the utmost importance for human beings to find out what the best conditions are for reaching the most perfect state possible. This is what the gardener tries to do for the plants, but it is even more important for humankind to do in regard to itself. The first question, then, is what kind of perfection a human being, as human, can reach. In answering this question, Aristotle observed that human beings, as social animals par excellence, can reach as individuals only some of the perfections possible for humans as such. Cats are more or less all alike in their functions; thus, each can fend for itself. With bees and termites, however, it is different. They are by nature divided into worker bees, drones, and queen bees, or worker termites, soldier termites, and queens. With human beings the differentiation of functions is much more subtle and varied. People can lead satisfactory lives only on the basis of a division of labor and distribution of functions. Some individuals are born with very great talents and inclinations for special kinds of activity. They will be happy and will make their best possible contribution to the life of the community only if they are permitted to follow this inclination. Others are less one-sidedly gifted and more easily adaptable to a variety of functions. These people can be happy shifting from one activity to another. This fact represents an enormous advantage the human species has over all other animals, because it enables it to adapt to all sorts of circumstances. But the advantage is paid for by the fact that no human individual is able to develop all of the perfections that are possible for the species as a whole.
There is another possible and, in its consequences, real disadvantage to such adaptability: the other animals, tightly confined to the limits set by nature, are crippled almost exclusively by external factors, but humans, in consequence of the freedom of choice granted to them through the variety of their gifts, can and very often do cripple and harm themselves. All human activities are directed toward the end of a good and satisfactory life. But there are many subordinate aims that are sensible ends only as far as they serve a superior end. There is, for example, no sense in producing or acquiring more shoes than can possibly be worn. This is self-evident. With regard to money, however, which has become exchangeable against everything, the illusion arises that it is good to accumulate it without limit. By doing so, humans harm both the community and themselves because, by concentrating on such a narrow aim, they deprive their souls and spirits of larger and more rewarding experiences. Similarly, an individual especially gifted for large-scale planning needs power to give orders to those capable of executing his plans. Used for such purposes, power is good. But coveted for its own sake, it becomes oppressive to those subdued by it and harmful to the oppressor because he thus incurs the hatred of the oppressed. Because of their imperfections, humans are not able to engage in serious and fruitful activities without interruption. They need relaxation and play, or amusement. Because the necessities of life frequently force them to work beyond the limit within which working is pleasant, the illusion arises that a life of constant amusement would be the most pleasant and joyful. In reality nothing would be more tedious.
Aristotle’s teleology seems to be based entirely on empirical observation. It has nothing to do with a belief in divine providence and is not, as some modern critics believe, at variance with the law of causality. It forms the foundation, however, of Aristotle’s ethics and political theory. Aristotle was an avid collector of empirical evidence. He induced his students, for instance, to study the laws and political institutions of all known cities and nations in order to find out how they worked and at what points their initiators had been mistaken regarding the way in which they would work. In later times, Aristotle came to be considered (and by many is still considered) a dogmatic philosopher because the results of his inquiries were accepted as absolutely authoritative. In reality, however, he was one of the greatest empiricists of all times.
Disciples and commentators
After Aristotle’s death his immediate disciples carried on the same kind of work, especially in the historical field: Theophrastus wrote a history of philosophy and works on botany and mineralogy, Eudemus of Rhodes (flourished before 300 bce) wrote histories of mathematics and astronomy, Meno wrote a history of medicine, and Dicaearchus of Messene (flourished c. 320 bce) wrote a history of civilization and a book on types of political constitutions. The next two generations of Peripatetics spread out in two directions: literary history, in the form of histories of poetry, epic, tragedy, and comedy, as well as biographies of famous writers, and physical science. Straton of Lampsacus (died c. 270 bce) created a new kind of physics based on experiments, and the great astronomer Aristarchus of Samos (c. 310–230 bce) invented the heliocentric system. The school then went for some time into eclipse until, in the 1st century ce, after the rediscovery of Aristotle’s lecture manuscripts, there arose a great school of commentators on his works, which had an enormous influence on medieval philosophy.